1. Technical Field
The invention relates to automatic test equipment (ATE) for testing integrated circuits.
2. Related Art
Today's integrated circuits require more precision voltage, higher resolution to the ATE to test its specification. Also higher speed is required to reduce its test time.
There are systems in the field, which allow for different accuracy levels. However, choosing a higher accuracy requires a prolonged testing time, because higher accuracy is achieved by means of lower sampling rates. Other systems which are directed to higher speed testing in turn achieve the reduced testing time by decreasing accuracy.
Additionally, digital-to-analog converters (DAC) used in ATE are subject to a linearity error, also called integrated linearity error or ILE. This error may cause voltage errors, current errors or distortion in the ATE system or module.
Hence, even if the resolution, i.e. the number of bits used for providing a digital representative of an analogue value, is extended, the actual resolution is very poor because of the linearity error.
Hence, it is a problem in the art to provide fast automatic test equipment which at the same time may offers high accuracy and/or increased linearity.